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06/27/2011 08:19:28 PM · #26 |
Originally posted by Bear_Music:
Nice piece of necromancy. One wonders if "neryn" happens to sell these lenses on e-bay or something, but what the heck... My main quibble with his exposition is how he suggests that the lens won't work for full-moon shots because DOF when focused at a quarter-million miles is not adequate to the task, LOL...
R. |
But at least he isn't having problems with Shudder speed..... |
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07/01/2011 01:06:41 PM · #27 |
Bought this lens about 6 months ago.
Here's why it is so cheap.
First the aperture is FIXED, and NOT adjustable. The difference in the f-stop is made only by the amount of ZOOM.
You can NOT adjust the aperture independently from the zoom. If the aperture could be adjusted, the problem below could be lessened.
The chromatic aberrations of this lens is HORRIBLE if you attempt to use it for any daylight shots.
Night shots (using a good tripod and bulb) do not seem to have as much of this problem. Don't zoom to close (see below).
The lens is CROOKED when extended, (yes I said crooked). When the lens is extended out, even when fully locked, the weight of the camera causes a bending effect. Surely this is going to make a HUGE difference on where the focal point will be on your sensor, creating even more distortion. The ONLY solution that MIGHT help is a separate tripod to support the camera.
Focus is an absolute bear with this lens unless you bring a HUGE monitor with you. You'll almost never get a decent focus with your viewfinder or lcd. Because of the fixed f-stop and the focus being so tight, you'll almost never get it right. The SLIGHTEST touch of the focus ring will move your focal point several feet making it extremely difficult to focus on your intended subject.
It is an O.K. lens if you can't put out the money for a better one, but so far as for professional use, FORGET IT.
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07/04/2011 10:59:30 AM · #28 |
I did not suggest I took a wild guess.
I must have tried a few hundred times before I gave up and just guessed as to why I could not get a "clear" shot
No I do not sell them on ebay I don't sell anything on ebay (go check same username its nerys not neryn) I am an ebay junky but for buying crap not selling it.
I bought my 800mm reflector 5+ years ago and I LOVE IT. its a fun lens that lets me get otherwise impossible shots.
I don't have $10 grand + to blow on some nice canon glass.
I THOUGHT the lens looked bent in one of those youtube videos !! (I do NOT have this particular lens I dismissed it because while more annoying the reflector solves that "huge length" problem. I feared for the mount on my camera. while I only have a puny XTI I can not afford to replace it :-)
and yes as you noted FOCUS is a really nasty problem. its SOO hard to get clean focus (the tiny viewfinder on my xti does NOT help)
that why its largely useless for action shots :-) for anything sitting still my method is this.
I find where the sweet spot "zone" is I go a bit past it and set the camera for motor drive and just hold the shutter down as I sweep through the sweet spot a few times.
every now and then I "get it" and you get an amazing crisp image. I can get close easy enough but that truly sharp nailed it shot is VERY elusive. but at $160. I don't care. its worth it.
Message edited by author 2011-07-04 11:05:28. |
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